if (isRetainPayload()) {
            final byte[] payload = new byte[len];
            System.arraycopy(buffer, start, payload, 0, len);
            setRawPayload(payload);
        }

        if (!verifySignature(buffer, start, len)) {
            throw new SMBProtocolDecodingException("Signature verification failed for " + getClass().getName());
        }

        this.length = len;

        if (isRetainPayload()) {
            final byte[] payload = new byte[len];
            System.arraycopy(buffer, 4, payload, 0, len);
            setRawPayload(payload);
        }

        if (!verifySignature(buffer, 4, len)) {
            throw new SMBProtocolDecodingException("Signature verification failed for " + this.getClass().getName());
        }

        return this.retainPayload;
    }

    @Override
    public byte[] getRawPayload() {
        return this.rawPayload;
    }

    @Override
    public void setRawPayload(final byte[] rawPayload) {
        this.rawPayload = rawPayload;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.internal.CommonServerMessageBlock#getDigest()
     */
    @Override